How do spiders reproduce?

Answer:

The typical sarcastic answer to this question is “very carefully!” Comedy and legend aside, spiders are frequently cannibalistic and a female would just as soon eat her mate as reproduce with him. Sometimes she does both. Sometimes the male sacrifices himself. The male redback spider of Australia, Latrodectus hasselti, somersaults into the jaws of the female after mating. This might help insure that it is his offspring she produces, rather than another male’s, by providing her with a substantial meal to aid in the development of her eggs. Male spiders usually “approach with caution,” however, literally sending strong signals to identify themselves as members of the same species. Jumping spiders and wolf spiders are well-known for dancing and drumming in specific patterns that leave no doubt as to their intentions. Even tarantulas communicate through rhythmic vibrations. Web-building spiders may enter the web of a female, plucking the threads in a way that differs from the frantic thrashing of an entangled prey item. Once a male spider succeeds in getting close enough, he does something remarkable: he plugs one of his pedipalps into one of the paired genital openings on the underside of the female’s abdomen. He previously secreted sperm from his abdomen onto a small web, then drew up the liquid into each pedipalp. Those modified appendages serve as “intromittent sex organs” that deliver the sperm to a female of the same species. His pedipalp fits so perfectly into the genital opening (epigynum) of his mate that it has been likened to a “lock and key” mating system that prevents cross-breeding between species. Once mating has been accomplished, he may leave part of his pedipalp inside his mate, preventing another male from mating with that female. Males of other species have different tactics to protect their investment of sperm. At least one secretes a kind of cement that seals the female’s genital opening, functioning like a spider chastity belt.